diff --git a/Sources/ZcashLightClientKit/Checkpoint/CheckpointSourceFactory.swift b/Sources/ZcashLightClientKit/Checkpoint/CheckpointSourceFactory.swift
index 53608891..ab190e1b 100644
--- a/Sources/ZcashLightClientKit/Checkpoint/CheckpointSourceFactory.swift
+++ b/Sources/ZcashLightClientKit/Checkpoint/CheckpointSourceFactory.swift
@@ -7,7 +7,7 @@
 
 import Foundation
 
-struct CheckpointSourceFactory {
+enum CheckpointSourceFactory {
     static func fromBundle(for network: NetworkType) -> CheckpointSource {
         BundleCheckpointSource(network: network)
     }
diff --git a/Tests/DarksideTests/AdvancedReOrgTests.swift b/Tests/DarksideTests/AdvancedReOrgTests.swift
index f973fcc1..d380e510 100644
--- a/Tests/DarksideTests/AdvancedReOrgTests.swift
+++ b/Tests/DarksideTests/AdvancedReOrgTests.swift
@@ -28,6 +28,10 @@ class AdvancedReOrgTests: ZcashTestCase {
     override func setUp() async throws {
         try await super.setUp()
         
+        mockContainer.mock(type: CheckpointSource.self, isSingleton: true) { _ in
+            return DarksideMainnetCheckpointSource()
+        }
+
         // don't use an exact birthday, users never do.
         self.coordinator = try await TestCoordinator(
             container: mockContainer,
diff --git a/Tests/DarksideTests/BalanceTests.swift b/Tests/DarksideTests/BalanceTests.swift
index 15c41e7f..88fe624b 100644
--- a/Tests/DarksideTests/BalanceTests.swift
+++ b/Tests/DarksideTests/BalanceTests.swift
@@ -26,6 +26,10 @@ class BalanceTests: ZcashTestCase {
     override func setUp() async throws {
         try await super.setUp()
         
+        mockContainer.mock(type: CheckpointSource.self, isSingleton: true) { _ in
+            return DarksideMainnetCheckpointSource()
+        }
+        
         self.coordinator = try await TestCoordinator(
             container: mockContainer,
             walletBirthday: birthday,
diff --git a/Tests/DarksideTests/BlockDownloaderTests.swift b/Tests/DarksideTests/BlockDownloaderTests.swift
index dd96e847..1e48d06f 100644
--- a/Tests/DarksideTests/BlockDownloaderTests.swift
+++ b/Tests/DarksideTests/BlockDownloaderTests.swift
@@ -10,7 +10,7 @@ import XCTest
 @testable import TestUtils
 @testable import ZcashLightClientKit
 
-class BlockDownloaderTests: XCTestCase {
+class BlockDownloaderTests: ZcashTestCase {
     let branchID = "2bb40e60"
     let chainName = "main"
 
@@ -21,10 +21,14 @@ class BlockDownloaderTests: XCTestCase {
     var storage: CompactBlockRepository!
     var network = DarksideWalletDNetwork()
     var rustBackend: ZcashRustBackendWelding!
-    var testTempDirectory: URL!
 
     override func setUp() async throws {
         try await super.setUp()
+
+        mockContainer.mock(type: CheckpointSource.self, isSingleton: true) { _ in
+            return DarksideMainnetCheckpointSource()
+        }
+        
         testTempDirectory = Environment.uniqueTestTempDirectory
 
         service = LightWalletServiceFactory(endpoint: LightWalletEndpointBuilder.default).make()
diff --git a/Tests/DarksideTests/DarksideSanityCheckTests.swift b/Tests/DarksideTests/DarksideSanityCheckTests.swift
index a7af5e4f..53bb6fe6 100644
--- a/Tests/DarksideTests/DarksideSanityCheckTests.swift
+++ b/Tests/DarksideTests/DarksideSanityCheckTests.swift
@@ -27,6 +27,10 @@ class DarksideSanityCheckTests: ZcashTestCase {
     override func setUp() async throws {
         try await super.setUp()
 
+        mockContainer.mock  (type: CheckpointSource.self, isSingleton: true) { _ in
+            return DarksideMainnetCheckpointSource()
+        }
+        
         self.coordinator = try await TestCoordinator(
             container: mockContainer,
             walletBirthday: birthday,
diff --git a/Tests/DarksideTests/PendingTransactionUpdatesTest.swift b/Tests/DarksideTests/PendingTransactionUpdatesTest.swift
index 42eb6276..e41d939d 100644
--- a/Tests/DarksideTests/PendingTransactionUpdatesTest.swift
+++ b/Tests/DarksideTests/PendingTransactionUpdatesTest.swift
@@ -25,6 +25,10 @@ class PendingTransactionUpdatesTest: ZcashTestCase {
     override func setUp() async throws {
         try await super.setUp()
 
+        mockContainer.mock(type: CheckpointSource.self, isSingleton: true) { _ in
+            return DarksideMainnetCheckpointSource()
+        }
+        
         self.coordinator = try await TestCoordinator(
             container: mockContainer,
             walletBirthday: birthday,
diff --git a/Tests/DarksideTests/ReOrgTests.swift b/Tests/DarksideTests/ReOrgTests.swift
index 4451c16c..b77722fd 100644
--- a/Tests/DarksideTests/ReOrgTests.swift
+++ b/Tests/DarksideTests/ReOrgTests.swift
@@ -44,6 +44,10 @@ class ReOrgTests: ZcashTestCase {
     override func setUp() async throws {
         try await super.setUp()
 
+        mockContainer.mock(type: CheckpointSource.self, isSingleton: true) { _ in
+            return DarksideMainnetCheckpointSource()
+        }
+        
         self.coordinator = try await TestCoordinator(
             container: mockContainer,
             walletBirthday: self.birthday,
diff --git a/Tests/DarksideTests/ShieldFundsTests.swift b/Tests/DarksideTests/ShieldFundsTests.swift
index 6b9f9a06..860953aa 100644
--- a/Tests/DarksideTests/ShieldFundsTests.swift
+++ b/Tests/DarksideTests/ShieldFundsTests.swift
@@ -25,6 +25,10 @@ class ShieldFundsTests: ZcashTestCase {
     override func setUp() async throws {
         try await super.setUp()
 
+        mockContainer.mock(type: CheckpointSource.self, isSingleton: true) { _ in
+            return DarksideMainnetCheckpointSource()
+        }
+        
         self.coordinator = try await TestCoordinator(
             container: mockContainer,
             walletBirthday: birthday,
diff --git a/Tests/DarksideTests/SynchronizerDarksideTests.swift b/Tests/DarksideTests/SynchronizerDarksideTests.swift
index 381d8d06..d69f04ae 100644
--- a/Tests/DarksideTests/SynchronizerDarksideTests.swift
+++ b/Tests/DarksideTests/SynchronizerDarksideTests.swift
@@ -30,6 +30,11 @@ class SynchronizerDarksideTests: ZcashTestCase {
 
     override func setUp() async throws {
         try await super.setUp()
+        
+        mockContainer.mock(type: CheckpointSource.self, isSingleton: true) { _ in
+            return DarksideMainnetCheckpointSource()
+        }
+
         let idGenerator = MockSyncSessionIDGenerator(ids: [.deadbeef])
         mockContainer.mock(type: SyncSessionIDGenerator.self, isSingleton: false) { _ in idGenerator }
         self.idGenerator = idGenerator
diff --git a/Tests/DarksideTests/SynchronizerTests.swift b/Tests/DarksideTests/SynchronizerTests.swift
index 73990e1a..33df28e1 100644
--- a/Tests/DarksideTests/SynchronizerTests.swift
+++ b/Tests/DarksideTests/SynchronizerTests.swift
@@ -26,7 +26,11 @@ final class SynchronizerTests: ZcashTestCase {
 
     override func setUp() async throws {
         try await super.setUp()
-
+        
+        mockContainer.mock(type: CheckpointSource.self, isSingleton: true) { _ in
+            return DarksideMainnetCheckpointSource()
+        }
+        
         // don't use an exact birthday, users never do.
         self.coordinator = try await TestCoordinator(
             container: mockContainer,
diff --git a/Tests/DarksideTests/Z2TReceiveTests.swift b/Tests/DarksideTests/Z2TReceiveTests.swift
index cdc5982b..5f91df81 100644
--- a/Tests/DarksideTests/Z2TReceiveTests.swift
+++ b/Tests/DarksideTests/Z2TReceiveTests.swift
@@ -28,6 +28,10 @@ class Z2TReceiveTests: ZcashTestCase {
     override func setUp() async throws {
         try await super.setUp()
 
+        mockContainer.mock(type: CheckpointSource.self, isSingleton: true) { _ in
+            return DarksideMainnetCheckpointSource()
+        }
+        
         self.coordinator = try await TestCoordinator(
             container: mockContainer,
             walletBirthday: birthday,
diff --git a/Tests/TestUtils/DarksideMainnetCheckpointSource.swift b/Tests/TestUtils/DarksideMainnetCheckpointSource.swift
new file mode 100644
index 00000000..808a2769
--- /dev/null
+++ b/Tests/TestUtils/DarksideMainnetCheckpointSource.swift
@@ -0,0 +1,35 @@
+//
+//  TestingCheckpoints.swift
+//
+//
+//  Created by Francisco Gindre on 2023-10-31.
+//
+
+import Foundation
+@testable import ZcashLightClientKit
+
+struct DarksideMainnetCheckpointSource: CheckpointSource {
+    private let treeState = Checkpoint(
+        height: 663150,
+        hash: "0000000002fd3be4c24c437bd22620901617125ec2a3a6c902ec9a6c06f734fc",
+        time: 1576821833,
+        saplingTree: "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",
+        orchardTree: nil
+    )
+
+    var network: NetworkType {
+        DarksideWalletDNetwork().networkType
+    }
+
+    var saplingActivation: Checkpoint {
+        treeState
+    }
+
+    func latestKnownCheckpoint() -> Checkpoint {
+        treeState
+    }
+
+    func birthday(for height: BlockHeight) -> Checkpoint {
+        treeState
+    }
+}